Fuel pump



June 4, 1935. A; M. BABITCH El AL 2,003,420

FUEL PUMP Filed 0611.26, 1955 2 Sheets-Sheet 1 250212411173 Zabizfb/vJune 4, 1935. M, BABlTCH ET AL I 2,003,420

FUEL PUMP Filed Oct. 26, 1933 2 Sheets-Sheet 2 Patented June 4, 1935UNITED 'STATES PATENT OFFICE FUEL PUMP Abraham M. Babitch and Gordon W.Harry,

Flint, Mich., assignors to A 0 Spark Plug Company, Flint, Mich., acorporation of Michigan Application October 26, 1933. Serial No. 695,314

13 Claims.

contain chambers constituting a variable volume pumping chamber, areceiving, filtering and sediment chamber, suitable valves and an airdome.

Other objects and advantages will be under.- stood from the followingdescription.

The application is in part a continuation of an application of Babitchand Harry for Fuel pump, Serial No. 642,342, filed November 12, 1932.

In the drawings: I

Fig. l is a longitudinal section through the p p- I Fig. 2 is a view online 2-2 of Fig. 1 with the cover removed and parts in section.

Fig. 3 is an exploded perspective of certain parts. Fig. fl is alongitudinal section'through a modifled form.

Fig. 5 is a section on line 5-5 of Fig. 4. Fig. 6 is a section on line6-6 of Fig. 5.

I Fig. 7 is a section on line of Fig. 4.

Referring by reference characters to Figs. 1-3

' inclusive, numeral 5 is the upper body member and 1 is the lowermember, these two members preferably formed by die casting. -Parts 5 andI. are secured together by fastening means 9, and clamp between them theperipheral portion of a gasoline impervious diaphragm The diaphragm issecured at its center to "a pumpstem |3'by means of discs l5 and IT anda nut l9 threaded to the stem.

The upper part 5 is recessed to form a variable volume pump chamberbetween the diaphragm H and a partition 2|. Above the partition the body5 is formed into another chamber 23 which is segmental in shape, beingclosed by a radial wall 25 extending from a central boss2'l to theperiphery.- From the central boss there is also a radial extensionconstituting a conduit 29 which merely extends through the segmentalchamber 23 but does not close it. An opening 3| 'in the wall of body 5communicates with the chamber 23. A screen 33 engages a shoulder on thetop of the peripheral part of body 5 and is held in place in thefollowing manner. A ring 35 is located above the peripheral part of thescreen as shown. A cover 31 is supported above the ring 35 and overliesits edge. An apertured cap 39 is threaded at its lower end into thecentral boss 21 and holds the cover in position. At the upper end of thecap 39 is a cup 4| constitutin an air dome. The screen, near its center,is seated on a shoulder of the central boss. The radial wall 25 has apassage extending therethrough from a point above the screen to thepumpcham- 5 her. Within the passage is a spring 43 seated on a shoulder45 and pressing upwardly .on a disc valve 41. which engages a valve seatconstituted by the lower end of a hollow threaded plug 49. The fluidfrom opening 3| enters the chaml0- .ber 23, is freed from foreign matterby the screen,

flows through the hollow plug 49, passes the valve 41, and enters thepump chamber. This flow of fluid is produced by the suction stroke ofthepump. Foreign matter which collects in the seg- 15 mental chamber 23beneath the screen 33 may be removed by a valve member 34.

The central boss isapertured as shown and Y carries a valve seat 5|. Thevalve seat 5| is engaged by a valve 53 normally held to its seat by 20any suitable resilient means such as 55. The

resilient means 55 engages a seat 56 held down by a spring 58. From thecentral boss an opening above the valve53 permits the flow of fluidthrough the passage in part 29. From this out- 25 let any suitableconduit may be provided to deliver the fuel to the carburetor of the.engine. j- The outflow of fluid is produced by the discharge stroke ofthe diaphragm.

The cam 51. which is on an engine cam shaft 59, operates to pushupwardlyon a rod 6|. Rod 6| engages a lever 63 which preferably may be oflaminated form as shown. The lever 63 is pivoted at 65 to the pumphousing. A spring 61 in abutment with a housing wall 69 engages thelever 63 and operates to hold the end of the rod 6| in contact with thelever and cam. It is through this partition 69 that the pump stem l3extends. ,The lever 63 has a lug 10 which may engage a pin 1| extendingbetween the arms 13 v of a second lever 15 also pivoted to the pumpcasing at 11. The outer end'of lever 15 has a known form of interlockingconnection with the pump stem l3 whereby theassembly of these parts maybe conveniently made.

. By the construction described an upward movement of rod 6| produced bythe cam rocks the lever 63 clockwise and when the lug 10 engages the pinH the lever 15 is rocked counterclockwise and the plunger and diaphragmexecute a suction stroke. In this way the fuel is drawn into the pumpchamber from the reservoir through the inlet valve 41. The dischargestroke is made by a spring 19. This spring is in abutment with thepartition 69 and the diaphragm disc l5. The

pump therefore has a variable stroke depending upon the built-uppressure in the pump chamber and the strength of spring 19. When thebuilt-up pressure in the pump chamber, resulting from a relatively smallconsumption of fuel, overcomes the spring 19, the lever 15 assumes aposition such that its pin H is engaged .by the lug 10 of lever 63 onlyat the latter part of the stroke of lever 63. The pump therefore has avariable stroke to supply fuel in accordance with the demands of theengine without the provision of means for bypassing or overflow.

This pump has special utility in those installations where rotation ofthe cam is such that a rod reciprocated thereby moves in a direction theopposite of that required by the diaphragm in making the suction stroke.The use of the two levers 63and 15 constitutes a very simple meanswhereby the necessary operation is effected. It will be understood thatthe lost motion present in this pump takes place between the ing 10 andthe pin 1I.

Referring now to the modified form shown by Figs. 4-7 inclusive, numeralI05 is the upper body member and I 01 the lower member. Parts I05 andI01 are secured together by fastening means I09 and clamp between themthe diaphragm H I. Pump stems I I3 and discs I I5 and I I1 correspond ina general way to parts I3, I5, and I1 in Fig. 1. In this modification inplace of nut I9 the end of stem H3 is headed as at II9 to hold the partsassembled.

The upper part I05 is recessed forming a pump chamber between thediaphragm III and the wall I2I which in this form is shown as a partseparable from the die. cast member I05. This part I 2| may be securedby fastening. means I20. Above the wall I2I the body I05 is formed intoanother chamber I23 which is segmental in shape and closed by a radialwall I25 extending from a hollow boss I21, the axis of which is somewhatoiTset from the axis of the bodyI05. The radial wall extends to theperiphery as shown. From boss I21 is a second radial extensionconstituting a conduit I 29. This conduit extends through but does notclose the chamber I23. An opening I3I in the wall of body I05communicates with cham-v ber I23. A screen. I33 engages a shoulder onthe top of body I05. A packing ring I35 is located above the peripheralregion of the screen. A

cover I31 is supported above ring I35 and overlies its edge. Y

The hollow boss I21 is closed at its upper end and at one side of itsaxis and in the axis of the body I05 is a screw-threaded opening I28. Afastening bolt I39 engages the cap I31 and is threaded into opening I28sufliciently. to hold the periphery of the cap firmly against theringI35 as shown by Fig. 4.

The radial wall I 25 has a passage I30 extending axially from the regionabove the screen to the pump chamber. Within this passage is a plug I49serving as a seat for a valve I41 held upwardly by a spring I43supported by an abutment I45 carried by the wall I2 I. The fluid fromopening I3I enters chamber I23, is freed-from foreign matter by thescreen, flows through the passage I30 and passes to the pump chamberthrough the valve I41. This flow of fluid is produced by the suctionstroke of the pump. Foreign matter which collects in chamber I 23beneath screen I33 may be removed by a plug I34.

Within the hollow chamber of boss I21 is an outlet disc valve I53normally held to a seat I 5|, provided on wall I2I, by a spring I55engaging a suitably mounted abutment I56. From the region above thisvalve I53 is an opening communicating with the outlet passage I29. Thespace within the boss above the valve I53 serves as an air to the pumpmember I01'and works against a spring I65 which serves to maintainconstant contact with the cam to prevent noise. Also pivoted on pivotI53 is a link I51. The end of link I61 has its end "I bent from theplane thereof and assembled with the pump stem- I I3 by being passedthrough a slot I13 therefor as shown by Fig. 7. By this arrangement thediaphragm assembly may be positioned to engage the end HI and thenrotated to the locked position shown by Fig. 7 prior'to the assembly ofthe top portion I05. The lever I6I has a shoulder I 15 to engage a partI11 of link. I61 whereby under the action of the cam the lever and linkmay swing as a unit and pull the stem I I3 and make a suction pumpstroke. The discharge is made by a spring I19 supported by the casingmember I01 and engaging the diaphragm plate I I5.

The operation of the pump will be understood without furtherexplanation. An important feature is the upper body part which isrecessed to form with the diaphragm a pump chamber; which carries thevalves; which is formed to provide a receiving, filtering and sedimentcollecting chamber; and which is provided with a self-contained airdome.

We claim: I

1. In a pump, a casing member provided with a recess, a movable pumpingmember cooperating with said recess to form a variable'volume pumpingchamber, said casing member also recessed to form a receiving chamber,said casing wall having an opening to said receiving chamber, a filterdividing said chamber into first and second parts, an axially extendingboss in the flrst part of said receiving chamber, a radial wallextending from said boss to the peripheral wall of said casing, saidboss and wall breaking the circular continuity of said first part ofsaid receiving chamber, inlet and outlet valves in said casing memberand communicating with said pumping chamber, said outlet valve being insaid boss, said boss above said outlet valve constituting an air dome,said radial wall having an axial passage communicating with the secondpart of the receiving chamber and with the pumping chamber by way ofsaid inlet valve, said casing having radial conduit means extending tothe wall thereof from a part of the boss above the valve.

2. The invention defined by claim 1, said axial boss having its axiscoincident with the axis of said casing member.

3. The invention defined by claim 1, said axial boss having its axisdisplaced from the axis of said casing member and closed at its endremote from the pumping chamber, a cap for the casing member forming theclosure for the second part of the receiving chamber. y

4. The invention defined by claim 1, said axial bosshaving its axisdisplaced from the axis of said F casing member and closed at its endremote from said pumping chamber, a cap for the casing member forming aclosure for the second part of the receiving chamber, and fasteningmeans holding the cap on said'casing, said fastening means located inthe axis of said casing and secured in the closed end of said boss.

5. In a pump, a casing member, a movable element, said member andelement forming a pumping chamber, said member also formed to constitutea reservoir, a wall extending radially within said reservoir andterminating in a. boss at a part of the wall removed from the casingperiphery, an inlet valve controlling communication between saidreservoir and pumping chamber, an outlet valve controlling fluid flowfrom the pumping chamber, said valves being located in said radial wall,the outlet valve being in said boss, means forming an air dome above aother casing member having a delivery passage from a position above saidoutlet valve, the radial said outlet valve to produce discharge at auniform rate of flow, and a cap for said casing member forming a closurefor said reservoir.

6. In a pump, a casing member provided with a recess, a movable membercooperating with said recess to form a variable volume pumping chamber,said casing member also recessed to 7. In a pump, a hollow casingmember, a partition, mechanism forming a pump below said partition, acentral boss in said casing member above the partition, inlet and outletvalves for said pump, the inlet valve forming a communication betweenthe space above the partition and the pump, one of said valves being insaid boss, 9. cover ior said casing member, an air I dome elementengaging saidcover and threaded into said central boss, said air domecommunicating with ,the space above said last-named valve. I 8. Theinvention defined by claim 7 togethe with a second casing member securedto and below said hollow casing member, a pump diaphragm between saidcasing members, means in said second casing member to operate saiddiaphragm, and means to secure said casing members together andperipherally clamp said diaphragm.

9. In a pump, cooperating casing members and a diaphragm clamped betweensaid members, pump operating means in one of said casing members, apartition with a central boss in the other casing member, the partitionand diaphragm constituting a variable volume pumping chamber, inlet andoutlet valves for said pumping chamber, the outlet valve being in saidcentral boss, a cover for said other casing member, a screenperipherally clamped between said other casing member and cover, an airdome member including an air dome 'to produce continuous flow threadedinto said boss over said outlet valve and operable to hold said coverand screen in position. I

10. In a pump, cooperating casing members and a diaphragmclamped'between said members, pump. operating means in one of saidcasing members, a partition in the other casing member, thepartition'and diaphragm forminga variable volume pumping chamber, aradial-wall above the partition forming a segmental reservoir, inlet andoutlet valves in said wall, one valve being in the center of the casing,a cover for said reservoir, a screen clamped between the casing memberand cover, an air dome element to produce a continuous flow secured tothe wall above said outlet valve and serving to hold said cover andscreen in position.

11 The invention defined by claim 10, said wall having a passage fromthe region above the screen to the pumping chamber below the partition,the inlet valve being in said passage, said other casing member having afluid admitting opening to the region below the screen.

12. In a pump, a casing member, a movable pump member, means to movesaid movable pump member, said member recessed at one end to form apumping chamber for said movable pump member, said casing having atransverse wall closing said recess, a radial wall in said casing memberabove said transverse wall and forming an arcuate receiving chamber,said casing having an opening communicating with said receiving chamber,said radial wall having a hollow, tubular boss at the end of the wallremoved from the periphery of the casing, said radial wall also having apassage parallel with the tube of said boss, inlet and outlet valves insaid passage and'tubular boss respectively, filtering means in saidreceiving chamber forming therein an upper region for clean fluid, saidparallel passage arranged to provide communication from said upperregion to said pumping chamber, and conduit means for the discharge offuel from said boss above said outlet valve, said hollow boss having anupper end closure to form an air dome above the outlet valve.

-18. In a pump, a casing member,v a movable pump member, means to movesaid movable pump member. said member recessed at one end to form apumping chamber for said movable pump member, said casing having atransverse gion for clean fluid, said parallel passage arranged toprovide communication from said upper region to said pumping chamber,and' conduit meansfor the discharge of fuel from said boss above saidoutlet valve, said hollow boss be-' ing integrally closed at its upperend to form an air dome above the outlet valve.

' ABRAHAM M. BABITCH.

